#include<stdio.h>
#include<stdlib.h>
typedef struct node{
    int data;
    struct node *left;
    struct node *right;
    }Node;
Node *root=NULL;
Node *create(int val){
    Node *newnode=(Node*)malloc(sizeof(Node));
    newnode->data=val;
    newnode->left=NULL;
    newnode->right=NULL;
    return newnode;
}
Node *insert(Node *root,int val){
if(root==NULL)
   return create(val);
   if(val < root -> data)
     root->left=insert(root->left,val);
     else
     root->right=insert(root->right,val);
     return root;
}
int Min(Node *root){
    if(root==NULL)
        return NULL;
    if(root->left==NULL)
        return root;
    return Min(root->left);
}
int main(){
    int n;
    scanf("%d",&n);
    if(n<0){
        printf("Invalid input");
        return 0;
    }
    int x;
    for(int i=0;i<n;i++){
        scanf("%d",&x);
        if(x<0){
        printf("Invalid input");
        return 0;
    }
        root=insert(root,x);
    }
    int min=Min(root);
    if(min!=NULL)
    printf("%d",min);
    return 0;
}